Preparing to interview Dr Dre is quite a nervy affair. Not only is he responsible for soundtracking gangsta rap, inventing G-funk, signing Eminem and reshaping hip-hop for the 90s, he also has a team around him seemingly desperate to make the experience as tense as possible.

A handful of journalists are driven downtown to Cult Studios on West 27th St in New York – a run-down space in mid-town which looks from the outside like, well, a squat (they've succeeded at looking inconspicuous) but inside is actually some kind of bling Tardis, with scantily clad promo girls giving out canapes to nibble on while we wait for The Doctor to arrive. One of his team warns me in conversation that he's a man of few words, answering technical questions in meetings with a simple thumbs up or thumbs down – and after seeing him in a press conference earlier where he spoke a mere two words ("thanks guys"), I believe what I'm told.

In recent years, Dre's branched out from music, becoming a successful international businessman with the birth of his Beats headphones range, a project which he has worked closely with head of Interscope records, Jimmy Iovine. So is he living the American Dream? He has no doubt. "Absolutely. I've been living the American Dream for over 25 years – just being able to do what I do, be creative and make money out of it, it's incredible."

Dre has certainly had a more creative hand in his line of Beats than a cynic would imagine. Iovine tells a story in the press conference of meeting Dre on the beach. Dre said he'd been approached to design a range of trainers, to which Iovine responded, "Fuck sneakers, let's make speakers". So they did. And Dre's been involved at every step – even harking back to hip-hop's early years in the new collection, which features a mobile beatbox designed to carry on your shoulder like a ghettoblaster. He talks about the project like his baby under a very simple premise: "I want people to enjoy music like I enjoy it in the studio, musicians have been hearing music differently for a long time and Beats are changing that".

Despite being flown to NYC to interview Dre ahead of the launch of this new range, I'm told that under no circumstance can I ask about his infamously long-awaited album Detox (It is testament to the brand he has become that Dre can keep the public eagerly waiting for a follow-up album to the legendary 2001 with no harm to his good name). Damn, I think, there goes the question on everybody's lips. As nice as they are, there's only so much I can bring myself to talk about headphones – what I want to know about, being a music journalist, is the music, not the earpieces you use to hear it. Unfortunately, a lot of my questions not relating to the product are cut short, so my allocated 10 minutes with Dre are punctuated with a PR's voice instructing me to "keep it Beats."

And yet, Dre is far from a sullen character. Before the interview, I stand outside and make small talk with him under the watchful gaze of his PR, and he manages to tell me that one UK act that he's listening to right now is the dubstep outfit Nero. He's so open and friendly, I wonder what all the fuss is about. The weight of the Dre legend is definitely felt by his team, though. The interview is conducted in a white room full of around 10 PRs, marketing managers and who-knows-who, and as a result the atmosphere is more than a little claustrophobic. At least he says more to me than he did in the conference, suddenly perking up about the project, adamant that he is not just a silent face of the brand.

"It's one of the best things I've ever been involved in" he says, laughing when I ask just how far he would take Brand Dre. Could he have a reality show like his long-time partner in hip-hop, Snoop Dogg on the cards? "No! In fact, I would advise against anyone doing reality shows. I won't be doing X Factor just yet."

I ask if his title as a businessman has overtaken the title of artist, "I don't think the brand has overtaken the music, I think that they just work together, like, I love watching the two come together."

We talk about how his journey has taken him from the streets of LA to the high-rise elevators of an international business mogul, and he says, with genuine modesty, that he's always surprised: "I could never have imagined where I am now." So has he let go of the anger that fuelled NWA? His PR steps in and insists, once more, that I "stick to questions about Beats." I want to scream.

I tell Dre how I saw a few kids wearing Beats on the subway earlier and he grins. "The ultimate experience is seeing young people in the headphones, almost as big as people listening to my album, well, listening to my album on the headphone would be pretty good too."

I try to talk about his influence on hip-hop culture and the awesome 2001, which my 14-year-old self played on repeat on my CD Walkman so that my mum wouldn't hear the unadulterated talk of bitches and hos but again, we're told to turn the questions back to headphones.

It's just surreal. What's funny, though, is that despite the pre-interview spiel from his "people" that tried to make speaking with Dre just a few steps down from an audience with God ("he's not doing any more interviews this year", "he doesn't speak a lot"), he actually comes across as modest, relaxed and entirely likeable, or at least not as intimidating as his build might suggest. Emboldened and frustrated, and with the PR theatrically tapping her watch, I decide to pose the question I've come 3,000 miles to ask. Lots have been cut short, I've been interrupted, and it's now or never.